Furniture locks, and particularly those suitable for simultaneously locking a plurality of stacked drawers, generally incorporate a reciprocative, vertically tracked locking bar. A plurality of lugs on each bar interferingly engage a blocking surface associated with each drawer in a locked position.
Typically, a keyed operator, through an intermediate linkage, effects translation of the slide bar which assumes, depending on the position of the key, either a locked or unlocked position. Exemplary of such a structure is that shown in U.S. Pat. No. 3,776,007, to Himsl. In Himsl, rotation about a first axis of a keyed operator directs an eccentric lug slidably within an elongate slot of a transverse rigid bar so that the bar is rotated. Vertical reciprocative motion of the slide bar is imparted from the rigid bar through an intermediate rocker arm. By turning the key, the lugs associated with the slide bar selectively either raise to seat in a locking bracket or lower to free the drawers for withdrawal.
The primary drawback with the Himsl mechanism is that very close tolerances are required in assembling the mechanism to assure proper alignment of coacting elements. Assembly of the locking system is complicated and the attendant costs thereby increased.
Further, given the typical, rigid, unitary nature of the prior art structures, each particular design is suitable for but a single desk or drawer configuration. Consequently closely dimensioned parts must be manufactured and inventoried to handle a wide range of desk constructions. Also, during use, the locking elements in the prior art, including those in the Himsl patent, might become misaligned thereby causing the locking system to malfunction.